Changeable message sign with single message display opening

Abstract

Movable message sign apparatus having a single message display opening, and a number of back-lighted message display members mounted within the opening. Each message display member includes a translucent message member having a pair of message faces which form an open V configuration. The message members are attached to end members that are pivotally mounted, so that there is no need for an axle extending through a message display member. The message display members are oscillated in unison between message display positions which place either a first set or a second set of message faces in message display alignment with the opening. A source of back lighting is provided at a sufficient distance behind the message members to avoid streaking or other localized intense illumination. Each message member has flanges which enhance the rigidity of the member and which prevent direct viewing of the illumination source.

I claim: 
     
       1. Changeable message, sign apparatus comprising: a housing defining a message display region and having a face defining a message display opening which is open to said message display region;   an array of separate elongated message display members disposed in said message support region for oscillation on respective parallel coplanar axes;   each of said message display members including a pair of illumination-transmissive message faces to form a message member having an open side, and additionally including separate end members attached to said message faces at opposite ends thereof;   each of said message display members being supported for oscillation in said message display region by pivot means which extend from said housing to said end members but which does not extend within said message member;   a separate source of illumination fixedly mounted within said housing behind and within said open side of each of said open message display members so that said message faces are back-lighted;   each of said illumination sources being elongated and disposed in substantially parallel alignment with the axis of rotation of a corresponding said message display member;   each of said illumination sources being located behind the corresponding axis of rotation of the respective message display member to provide substantially uniform internal illumination of said message faces; and   each of said message faces having a flanged extension portion extending a distance rearwardly from an unsupported longitudinal edge thereof in substantially parallel alignment with the confronting undisplayed message face of the adjacent message display member, so that said flanged extension portions block direct illumination which would otherwise pass from said illumination sources through gaps between said message display members during oscillation between first and second message display positions, without interfering with adjacent message display members during said oscillation; and   means operatively connected to each of said message display members for oscillating each of said message display members in unison about said axes to either a first message display position, whereat a first face of each said message member is aligned in said message display opening, or to a second message display position, whereat a second face of each said message member is aligned in said message display opening;   each of said message faces including said flanged extension portion comprises a unitary member which is connected between said separate end members of said message display members, whereby said flanged extensions provide enhanced torsional stiffness for each message member;   each said elongated illumination source is longer than the corresponding message display member; and   each of said end members of said message display members has a pair of recesses which accommodate said illumination source without interference as said message display member oscillate.   
     
     
       2. Apparatus as in claim 1, wherein said oscillating means comprises: a first link pivotably connected to each end member at one end of each said message display member;   a second link pivotably connected to each end member at the other end of each said message display member; and   motive means connected to oscillate said first and second links in unison to move said end members and the attached message members between said first and second message display positions.   
     
     
       3. Apparatus as in claim 2, wherein said motive means comprises a torque tube to be driven for oscillation and connected to oscillate each of said links. 
     
     
       4. Apparatus as in claim 1, wherein: each of said message faces at the attachment to said end member comprises a side of an equilateral triangle; and   said pivot means are disposed at the centroid of the respective said equilateral triangles.   
     
     
       5. Apparatus as in claim 1, wherein: said message faces of each message support member are offset with respect to the rotational axis of each corresponding message display member so that a gap exists between an edge of said housing face and a particular message face of the adjacent message display member in one of said message display positions; and   said particular message face of each said adjacent message display members is extended to occupy said gap.